This invention relates to a flexible disk drive, in particular, to a front shutter structure thereof.
The flexible disk drive defines a loading slot for loading a flexible (magnetic) disk. Generally, to the loading slot, a single swing front shutter is attached. The front shutter always receives turning force (or resilience) from a shutter spring in a closing direction. Insertion of the flexible disk into the flexible disk drive is made by pushing open the shutter against the resilience of the shutter spring.
A related flexible disk drive comprises a front shutter and a main frame with a pair of supporting plates for rotatably supporting the-front shutter.
The front shutter of the related flexible disk drive comprises a door portion having an approximately rectangular board shape, and a pair of shaft portions which are formed at both ends of a long side of the door portion and which project from the door portion. The shaft portions have a common center axis and serves as a pivot for swing of the door portion. At bases of the shaft portions, positioning portions are formed. The positioning portions restrict movable range of the door portion in a direction along the pivot when the front shutter is attached to the related flexible disk drive.
On the other hand, the supporting plates of the related flexible disk drive are opposed to each other and define holes which are inserted with the shaft portions of the front shutter. The positioning portions of the front shutter have an outside diameter larger than an inside diameter of the holes of the supporting plates. Accordingly, the supporting plates rotatably support the front shutter in a state where only the shaft portions of the front shutter are inserted into the holes of the supporting plates.
As mentioned above, the related flexible disk drive includes the positioning portions formed on the front shutter to restrict the movable range of the front shutter in the direction along the pivot. A distance between top sides of the positioning portions is slightly shorter than an interval between the supporting plates for supporting the front shutter. That is, a narrow gap is remained between one of the positioning portions and one of the supporting plates when the other of the positioning plates is close into contact with the other of the supporting plates. The gap between the positioning portion and the supporting plate allows the front shutter to swing smoothly.
However, the gap between the positioning portion and the supporting plate is easy to be eliminated by a little deformation of the supporting plates (or the main frame). Absence of the gap between the positioning portion and the supporting plate makes swing of the front shutter difficult or impossible. That is, the supporting plates are in contact with the positioning portions simultaneously and impede the swing of the front shutter.
Thus, the related flexible disk drive has an apprehension that the little deformation of the supporting plates or the main frame makes the swing of the front shutter difficult or impossible.